Sagebrush makes an interesting point about the USFS areas that might surround some National Parks.
I see Yosemite NP is surrounded with four forests: Stanislaus, Humbolt-Toyabe, Inyo, and Sierra.
Sequoia & Kings Canyon NP to the south is also surrounded by Inyo and Sierra NF.
However, if you read paragraph four here:
Unmanned Aircraft Systems FAQs | US Forest Service it appears the USFS has not yet implemented anything with hobbyists drones including taking off and landing on their land....yet. If a TSR is in place, you are toast to even fly there (e.g. Forest fire areas that have about a three month lock-out.).
I'm sort of surprised about this as I applied for a still photo permit this year on USFS land and gave up after it exceeded $2,000 and part of that was some idiotic $1,600 Parking Encroachment Permit from the local county whose roads dept. maintains the forest service roads where you can normally park for $5 per day. Some symbiotic relationship going on between the city, county, and the feds. There was some additional fee for aerial which also included a high liability of about $5 million too. Why the drone isn't in the above link with their a-la-cart fees I don't know, but in their permit process it sure is.
Entire law thing is a very gray area. Some say you can. Some say you can't. Some say you can if you pay us then you're okay. Depends on the po-po of the day you talk too I guess, and what side of the bed they got out of. Some seem to need "Public contact hours" so kicking you out of anything justifies their job if they cannot extort cash from your wallet.
Mack